Debian Corefiles

If you have any issues with programs segfaulting, it can be useful to allow coredumps in order to see what happened.

You first have to allow coredumps

vi /etc/security/limits.conf

*  –  core  100000

@users  –  core  0

core is measured in kbytes, and core files can be fairly large (the simple script below generates a 350kb file).  Do not set this to unlimited for regular users!

echo 1 > /proc/sys/kernel/core_uses_pid

mkdir /tmp/core

echo “/tmp/core/dump” > /proc/sys/kernel/core_pattern

ulimit -c 100000

To test it let’s create a script that will cause a coredump.

vi core_dump.sh

#!/bin/bash
#core_dump.sh
kill -s $$
#end

chmod +x core_dump.sh
./core_dump.sh

ls /tmp/cores

dump.14594 core_dump.sh

To view the corefile, you need gdb.

apt-get install gdb

gdb -c dump.13594